1. Field of the Invention
The present invention relates generally to an antenna for portable wireless communication apparatuses, and more particularly to an improved antenna for the prevention of harm to users by electromagnetic waves generated by portable wireless communication apparatuses.
2. Description of the Prior Art
Today, mobile phones and other wireless apparatuses have been widely used due to the development of the communication service, and such communication apparatuses can be used everywhere by means of wireless communication technology.
In general, communication can mainly be classified into wire communication and wireless communication. In the case of wireless communication, there are needed a transmitter for transmitting electromagnetic waves, an antenna for receiving the electromagnetic waves transmitted from the transmitter, and a receiver for receiving the electromagnetic waves from the antenna.
The transmitter-receiver and the antenna are installed on the body of the communication apparatus. Since these devices, such as the transmitter-receiver and the antenna, have become smaller and lighter, the communication apparatuses including these device have been miniaturized.
The antenna can be classified according to the operation method of a linear radiator and a helical antenna part in which the radiating directions of the electromagnetic waves are non-directional. That is, the antennas are mainly classified into three types, that is, a retractable type, a fixed type and a top mounted-helical type. In the retractable type of antenna, the helical antenna part 100 is fixed to the housing and the linear radiator 200 can move up and down in the helical antenna part 100, as shown in FIG. 10a. In the fixed type of antenna, both helical antenna part 100 and linear radiator 200 are fixed to the housing, as shown in FIG. 10b. In the top mount-helical type of antenna, the helical antenna part 100 is installed on top of the linear radiator 200, as shown in FIG. 10c. 
As described above, if the helical antenna part in which the radiating directions of electromagnetic waves are non-directional is used, the antenna has direct harmful effects on the user of the wireless communication apparatuses. The electromagnetic waves of the antenna include direct waves, reflected waves and diffracted waves. All these waves do harm to people, and above all the direct waves are the most harmful.
A conventional electromagnetic waves intercepting system encloses a circuit substrate mounted in the communication apparatus so as to prevent the electromagnetic waves from leaking to the outside. This conventional electromagnetic waves intercepting system has a problem in that the electromagnetic waves leak to the outside through an antenna connecting hole which is formed in the electromagnetic waves intercepting system.
That is, this conventional electromagnetic waves intercepting system includes the hole in which the antenna connector is installed so as to ground the antenna exposed to the outside on the circuit substrate of the communication apparatuses. When the antenna connector is connected to the hole, the hole is not completely sealed due to the tolerance of the hole.
According to another conventional method for intercepting electromagnetic waves, a filter material for intercepting the electromagnetic waves is coated onto the inside of the casing so as to intercept the electromagnetic waves.
However, since the conventional wireless antenna is positioned on the upper side of the casing of the communication apparatuses and is pulled from a guide protrusion to make a phone call, the electromagnetic waves radiated when using the communication apparatuses are directly transmitted to the head of the user. Thus, the health of the user becomes worse because the direct waves, the reflected waves and the diffracted waves have a direct negative influence upon the head of the user.